Circulating-air-cooled block



Dec. 31, 1929. J. E. ANDERSQN 1,741,180

CIRCULA'IING AIR COOLED BLOCK Filed Jan. 23. 1928- 2 Sheets-Sheet 1 Dec- J. a ANDERSON 1,741,130

I CIRCULATING AIR COOLED BLOCK Filed Jan. 25. 1928 2 Sheets-Sheet 2 d fizw a depth of from five hand fired jobs Patented Dec. 31, 1929 UE'I'ED STATES PATENT orFicE JOHN E. ANDERSON, OF CHICAGO, ILLINOIS, ASSIGNOB TO ELIBRICO JOINTLESS FIRE- CIRGULATING-AIR-OOOLED BLOCK Application filed January 23, 1928. Serial No. 248,620.

This invention relates to furnace construction and a block therefor, and more particularly to what I term a circulating air cooled block adapted for use in boiler furnaces and the method of combining this block with the furnace structure.

In boiler furnaces difficulty is experienced due to erosion of the side walls of the furnace, these walls being frequently eroded to to eight inches after being in use for but a short period of time. This erosion occurs along the grate line and is caused by green fuel being pushed to the side walls and allowed to coke, which happens in where heavy fires are carried or the coking method is followed, and in certain types of stokers. The green fuel at the sides of the lire bed does not obtain sufficient air to support combustion with the result that this fuel cokes against the side walls with a destructive chemical action thereto and clinkers form, the removal of these clmkers adding to the destruction of the side walls of refractory material. Attempts have been made to overcome this objection by providing air admission openings above the grate at the sides of the furnace, a1r being supplied to these openings by sultable means. In this manner combustion is obtained at the sides of the fuel bed preventing coking of the fuel and consequent destruction of the walls. One method of supplying air at the sides of the fuel bed is by means of blocks provided with air admission openings through their inner faces.

5 While this method has proved satisfactory in some respects, it is open to the objection that the air admission openings of the blocks become quickly clogged and, in many instances, completely stopped due to the slag entering such openings. As a result, the means for supplying the combustion supporting air to the sides of the fuel bed soon be comes materially reduced in efficiency or, in some cases, altogether inefficient. I have found that these objections can be avoided by providing a block so constructed that the air admission openings are effectively protected in such manner as to direct the slag and other materials of the fire bed away from such openings in such manner as to prevent possibility of clogging thereof.

In accordance with my invention, I provide a block having air admission openings extending through its inner face, the block being also provided with elements projecting inwardly beyond and above the openings and with elements inclined downwardly and inwardly toward the grate structure below the openings, these various elements being so disposed and related as to effectually prevent entry of slag or other materials into the openings whereby clogging thereof is eliminated. This block is also so constructed that each block forms in itself a complete unit whereby the blocks may be arranged in the furnace structure so as to provide a continuous air admission structure or, if desired, may be disposed in spaced relation, as conditions may require. The block constructed in this manner is particularly well adapted for incor poration in furnaces which have already been built without necessitating any material changes in the structure thereof, and are also adapted for use in newly constructed furnaces of known construction. Further objects and advantages of my invention will appear from the detailed description.

In the drawings:

Figure 1 is a fragmentary perspective view of a furnace wall, showing blocks constructed in accordance with my invention as applied,

the grate structure being indicated by dotted lines;

Figure 2 is'a fragmentary sectional view taken substantially on line 2--2"of Figure 1; Figure 3 is a perspective inner face View of theblock; and

Figure 4c is a perspective outer View of the block.

The block 1 is formed of suitable refractory material and is substantially cubiform. This block includes a front wall 2 of rectangular shape from which projects a rearwardly extending wall or flange 8 forming with front wall 2 an air receiving space or chamber 4. This flange is provided through its bottom wall with an air inlet opening 5 through which air is supplied to the space l in a suitable manner. The block is provided face or back in the front wall thereof with a plurality of channels which are disposed horizontally, that is, parallel to the plane of the air inlet opening 5. Each of the channels has a top wall 6 which is perpendicular to the face of the block, and a lower wall 7 which is inclined downwardly away from the block, that is, downwardly toward the grate of the furnace when the block is in position. The walls 6 and 7 are connected by a flat vertical wall 8 of appreciable height. Air admission openings 9 extend through the wall 2, the inner ends of these openings extending through the vertical walls 8 of the channels so as to be disposed closely adjacent and beneath the overhanging top or upper walls'6 of the channels. As will be noted more clearly from Figures 1 and 2, the upper walls 6 project inwardly well beyond the inner ends of the openings 9 and serve to effectually prevent entry of material from the fire bed into these openings from above the same.

I have shown the block as applied to a furnace structure including a wall 10 of the setting of known construction and a grate structure 11 also of known construction. The wall 10 includes an inwardly extending or thickened portion 12 forming a shoulder or bench upon which the blocks 1 are placed, these blocks being disposed to extend above the grate 11 a distance corresponding to the greatest thickness of the fire bed f. The blocks are disposed with the air inlet openings 5 downwardly and these openings register with the upper ends of inclined air inlet ducts 13 formed in the inner portion or bench 12 of wall 10. These air ducts supply air to the air space or chamber 4 of the block from beneath the grate,and this air flows through the air admission openings 9 into the fire bed from the sides thereof, thus assuring combustion at the sides of the fire bed. This prevents coking of the fuel and consequent injury to the side walls of the furnace. It will be noted that the air inlet openings 9 are disposed horizontally so that the air flowing therethrough is discharged into the fire bed in proper direction to promote combustion therein without tending to interfere in an way with air flowing upwardly through the grate 11.

It will be noted that the block 1 is of substantially box-like structure and forms a complete unit in itself, so that the blocks may be mounted adjacent each other or may be spaced apart, as conditions require. I have shown the blocks as disposed adjacent each other, the channels of these blocks being in register to form, in effect, continuous channels along the sides of the furnace so that combustion supporting air is discharged through the openings 9 into the fuel bed for the full length thereof. Due to the particular formation of the channels in the inner faces of the blocks, slag and other materials of the fuel bed are effectively prevented from entering the air admission openings from above the same and any materials which may tend to collect upon the inclined lowerwalls 7 of the channels will be directed thereby downwardly toward the grate and away from the air admission openings. There is thus a very definite reation and co-operation between the position of the block and the formation of the channels therein, and the grate structure, the blocks being mounted -to dispose the channels thereof parallel with the grate structure, that is, horizontally so that these channels prevent clogging of the air admission openings in the manner stated.

The wall 10, above the blocks 1, is provided with a suitable refractory lining 14. This lining maybe of any suitable material though 1 preferably employ a lining which is built up from a composition in a plastic condition and is then dried and vitrified so as to form a monolithic lining. The blocks 1 are, also, preferably formed of the same material as the lining 14.- though any suitable or preferred refractory material may be used for both the block and the lining. It will also be evident that air under pressure can be supplied to the air spaces or chambers of the blocks to produce a forced draft when desired or conditions may require, and I contemplate the use of a forced draft, as well as of a natural draft-such as that illustrated and described.

,Vhat I claim is:

1. As a new article of manufacture, a re-' fractory block comprising a front wall provided in its inner face with spaced channels each having an upper wall substantially perpendicular to the face of the block and a lower wall inclined downwardly away from the block, each channel also including a flat inner wall connecting said top and bottom walls, the block being provided with air admission openings extending therethrough and through the fiat inner walls of the channels.

2. In combination with a furnace includ ing a wall and a grate structure, blocks mounted at the inner face of a wall above v v and adjacent the grate structure, said blocks being provided in their inner faces with horizontal channels, each channel having an upper wall perpendicular to the face of the block and a lower wall inclined downwardly toward the grate, each channel also having a vertical inner wall connecting said upper and lower walls, the blocks being provided with air admission openings extending through the inner faces thereof and opening through the vertical walls of the channels, and means for supplying air to said openings.

3. In combination with a furnace including a wall and a grate structure, hollow blocks mounted at the inner face of the wall above and adjacent the grate structure, said blocks being provided in their inner faces per and lower walls,

with horizontal channels, each channel having an upper wall perpendicular to the face of the block and a lower wall inclined downwardly toward the grate, each channel also having a vertical inner wall connecting sa1d upper and lower walls, the blocks having air admission openings extending through the inner faces thereof and opening through the vertical walls of the channels, each of the blocks having an air inlet opening through its bottom wall and the furnace wall being provided with air supply ducts communicating with said inlet openings and with the space beneath the grate structure.

4. In combination in a furnace comprising a wall provided with air supply ducts and a grate, hollow blocks seating upon the wall at the grate and having air inlet openings cominunicating with said ducts, said blocks being provided in their inner faces with horizontal channels each of which has an upper wall perpendicular to the face of the block and a lower wall inclined downwardly toward the grate and a vertical wall connecting said upsaid blocks having air admission openings extending through the inner faces thereof and opening through the vertical walls of the channels, said openings being in the plane of the firebed on the grate.

5. In combination in a furnace comprising a wall and a grate structure, blocks mounted at the inner face of the wall adjacent the grate and extending above the same, the blocks being provided in their inner faces with. horizontal grooves each having an upper wall perpendicular to the inner face of the block and a lower wall inclined downwardly toward the grate and a vertical inner wall connecting said upper and lower walls,

' the blocks being provided with air admission openings extending through the inner walls of the grooves thereof, the grooves and said openings being disposed in the plane of the firebed supported upon the grate, and means for supplying air to said air admission openmgs.

In Witness whereof, I hereunto subscribe my name this 12th day of January, 1928.

J. E. ANDERSON. 

